This invention relates to a diverter valve for pneumatic conveying systems, and in particular, to a slide diverter valve having an improved seal arrangement.
Bulk dry materials in a pelleted, granular and/or powdered form are frequently transported in a pneumatic conveying system from one point to another. In such conveying systems, the material to be conveyed is suspended in an airstream and the suspension is moved by either air pressure or a vacuum. The air thereby acts as a conveying medium for the material, and carries the same through a plurality of interconnected pipes or conduits which extend from the source of the material to the area into which the same is to be deposited.
Diverter valves are installed in the pneumatic lines to selectively control the flow of the material therethrough, and are adapted to intermittently direct the material flow from one line into two or more separate lines. If the valve does not form a secure seal between the various lines, the valve will leak and thereby permit a portion of the conveyed material to escape from the lines. This results not only in a loss of the material which is oftimes expensive, but also presents substantial housekeeping problems, particularly where the substance being conveyed is toxic, and/or particularly difficult to clean. Further, an improper valve seal results in a loss of line pressure or vacuum, thereby reducing the efficiency of the conveying system, and can also cause contamination of the material being conveyed.
The principal objects of the present invention are: to provide a diverter valve for pneumatic conveying systems having a secure seal for interconnecting various material conveying conduits; to provide such a diverter valve of the parallel sliding plate type having a seal ring mounted in a mating groove in one of the plates to prevent loss of conveyed material and/or line pressure, as well as alleviate contamination of the conveyed material and assist in neat housekeeping; to provide such a diverter valve wherein the seal ring includes inner and outer grooves in which a resilient seal ring is mounted and seals against associated groove surfaces; to provide such a diverter valve wherein the seal ring is urged resiliently into a sealing condition by air pressure; to provide such a diverter valve having an anti-friction plate positioned between the sliding plates for durable and reliable sealing action; to provide such a diverter valve wherein the plates are mutually translated by a pneumatic cylinder for convenient, safe and efficient operation; to provide such a diverter valve wherein the pneumatic cylinder is pivotally mounted in a valve frame for nonbinding translation of the mating valve plates; and to provide such a diverter valve which is economical to manufacture, efficient in use, capable of a long operating life, and particularly well adapted for the proposed use.
Other objects and advantages of this invention will become apparent from the following description taken in connection with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention.
The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.